A lighting unit in which various light sources used in electronic devices are utilized has been implemented in such a manner as to increase light efficiency by utilizing an appropriate light source according to each property of the electronic devices.
The lighting unit used in the electronic devices has recently been variously applied to a backlight unit applied to a flat display, an indoor light used in indoor environments, a headlight, a fog light, a backlight, a sidelight, a license plate light, a taillight, a stop light, a turn signal light, and a hazard flasher lamp, which are installed at the outside of a vehicle, an indoor illumination lamp installed inside a vehicle, and the like.
Most of such lighting units are mainly realized by a method of increasing luminance of a surface light source by applying a member such as a light guide plate for enabling the efficient transmission of light.
However, when the surface light source is to be mounted in various places such as a vehicle lamp, it is not easy to create a design for mounting the surface light source, and it is difficult to satisfy AMECA Standard in North America for the purpose of export overseas.
In addition, due to the limit of the lighting unit to have a certain standard and configuration, it is difficult to implement the lighting unit in a slimming structure while ensuring a desired uniformity of light in a limited place.